Evidence map›Paper›PMID 34657602›Full record

ArticleMalaria journal2021

Purification of native histidine-rich protein 2 (nHRP2) from Plasmodium falciparum culture supernatant, infected RBCs, and parasite lysate.

Balwan Singh, Jessica N McCaffery, Amy Kong, Yong Ah, Scott Wilson, Sayan Chatterjee, Deepak Tomar, Michael Aidoo, Venkatachalam Udhayakumar, Eric Rogier

Open access · goldAbstract read
In one paragraph

Article in Malaria journal, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
0.2field-weighted citation impact, top 42% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed, 1 citations in OpenAlex.

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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors at 2 institutions in 1 country.

Balwan Singh *Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30329, USA.
Jessica N McCaffery *Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30329, USA.
Amy KongMalaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30329, USA.
Yong AhMalaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30329, USA.
Scott WilsonMalaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30329, USA.
Sayan ChatterjeeIHRC, Inc, Atlanta, GA, 30346, USA.
Deepak TomarDepartment of Medicine, Division of Rheumatology, Emory University, Atlanta, GA, USA.
Michael AidooMalaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30329, USA.
Venkatachalam UdhayakumarMalaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30329, USA.
Eric RogierMalaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA, 30329, USA. erogier@cdc.gov.ORCID http://orcid.org/0000-0001-7375-8304
Centers for Disease Control and Prevention · USEmory University · US

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundDespite the widespread use of histidine-rich protein 2 (HRP2)-based rapid diagnostic tests (RDTs), purified native HRP2 antigen is not standardly used in research applications or assessment of RDTs used in the field.

methodsThis report describes the purification of native HRP2 (nHRP2) from the HB3 Plasmodium falciparum culture strain. As this culture strain lacks pfhrp3 from its genome, it is an excellent source of HRP2 protein only and does not produce the closely-related HRP3. The nHRP2 protein was isolated from culture supernatant, infected red blood cells (iRBCs), and whole parasite lysate using nickel-metal chelate chromatography. Biochemical characterization of nHRP2 from HB3 culture was conducted by SDS-PAGE and western blotting, and nHRP2 was assayed by RDT, ELISA, and bead-based immunoassay.

resultsPurified nHRP2 was identified by SDS-PAGE and western blot as a - 60 kDa protein that bound anti-HRP-2 monoclonal antibodies. Mouse anti-HRP2 monoclonal antibody was found to produce high optical density readings between dilutions of 1:100 and 1:3,200 by ELISA with assay signal observed up to a 1:200,000 dilution. nHRP2 yield from HB3 culture by bead-based immunoassay revealed that both culture supernatant and iRBC lysate were practical sources of large quantities of this antigen, producing a total yield of 292.4 µg of nHRP2 from two pooled culture preparations. Assessment of nHRP2 recognition by RDTs revealed that Carestart Pf HRP2 and HRP2/pLDH RDTs detected purified nHRP2 when applied at concentrations between 20.6 and 2060 ng/mL, performing within a log-fold dilution of commercially-available recombinant HRP2. The band intensity observed for the nHRP2 dilutions was equivalent to that observed for P. falciparum culture strain dilutions of 3D7 and US06 F Nigeria XII between 12.5 and 1000 parasites/µL.

conclusionsPurified nHRP2 could be a valuable reagent for laboratory applications as well as assessment of new and existing RDTs prior to their use in clinical settings. These results establish that it is possible to extract microgram quantities of the native HRP2 antigen from HB3 culture and that this purified protein is well recognized by existing monoclonal antibody lines and RDTs.

Indexed as

Antigens, ProtozoanBlotting, WesternElectrophoresis, Polyacrylamide GelEnzyme-Linked Immunosorbent AssayErythrocytesHumansImmunoassayMalaria, FalciparumMicrospheresPlasmodium falciparumProtozoan ProteinsQuality ControlTime FactorsAntigens, ProtozoanHRP-2 antigen, Plasmodium falciparumProtozoan ProteinsAntigenHistidine-rich protein 2 (HRP2)Plasmodium falciparumProtein purification

Identifiers

PMID34657602
PMCPMC8522059
OpenAlexW3183817931

What OpenQuestion holds

Textmetadata
LicenceCC BY
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Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.